Merge from 2_3 branch

lib/python/App/dtml/manage_page_header.dtml

@@ -5,7 +5,8 @@
 <title><dtml-if title><dtml-var title></dtml-if></title>
 <dtml-let ag="REQUEST.get('HTTP_USER_AGENT', '')"
      is_nav4="ag[:9] == 'Mozilla/4' and _.string.find(ag, 'MSIE') < 0"
-     use_css="REQUEST.get('zmi_use_css', '1')">
+     use_css="REQUEST.get('zmi_use_css', '1')"
+     zmi_embedded_css="1">
 <dtml-if use_css>
 <dtml-if is_nav4>
 <style type="text/css">

lib/python/App/dtml/manage_page_style.css.dtml

+<dtml-unless zmi_embedded_css>
 <dtml-call "RESPONSE.setHeader('Content-Type','text/css')">
+</dtml-unless>
 h1 {
   font-family: Verdana, Helvetica, sans-serif; 
   font-size: 24pt; 

lib/python/App/dtml/zope_quick_start.dtml

@@ -4,7 +4,8 @@
 <meta http-equiv="content-type" content="text/html; charset=iso-8859-1">
 <title>Zope QuickStart</title>
 <dtml-let ag="REQUEST.get('HTTP_USER_AGENT', '')"
-     is_nav4="ag[:9] == 'Mozilla/4' and _.string.find(ag, 'MSIE') < 0">
+     is_nav4="ag[:9] == 'Mozilla/4' and _.string.find(ag, 'MSIE') < 0"
+     zmi_embedded_css="1">
 <dtml-if is_nav4>
 <style type="text/css">
 <!--